1. Field of the Invention
This invention relates to a flywheel device which has at least two inertial masses which can rotate relative to one another. The inertial mass device also comprises a damping device which damping device comprises elastic elements which elastic elements act against the rotation of the inertial masses with respect to one another. The output side inertial mass is guided both radially and axially by a bearing arrangement with respect to the input side inertial mass, which bearing assembly comprises at least one axial plain bearing and at least one radial plain bearing. The input side inertial mass can be, for example, connected to the crankshaft of an internal combustion engine.
2. Background Information
German Patent No. 34 11 092 C2 describes a known inertial mass device which has two inertial masses which can rotate relative to one another against the action of elastic elements which are in the form of coil springs of a damping device. One of these inertial masses, namely the output-side inertial mass, is guided by means of a bearing arrangemt both radially and axially with respect to the input-side inertial mass, whereby the bearing arrangement has an axial plain bearing and a radial plain bearing. While the axial plain bearing is clamped between the crankshaft of an internal combustion engine and an axial center or pilot stud which is realized on the second inertial mass, the radial plain bearing is located between a hub which is realized on the input-side inertial mass and faces the output-side inertial mass and the above-mentioned center stud, and therefore surrounds the axial plain bearing.
As explained in greater detail in the descriptive portion of this above-mentioned patent, the two inertial masses are axially clamped together or are axially biased toward one another. Consequently, wobbling movements which occur on the crankshaft of the internal combustion engine are transmitted not only to the input-side inertial mass which is fastened to this crankshaft, but also to the output-side inertial mass which, as indicated above, comes in contact with the crankshaft via the axial plain bearing, namely on account of the clamping under an axial force. The radial plain bearing between the two inertial masses is thereby protected, of course, because there are no sharp edges on it, but the wobbling movements are transmitted without filtration to the output-side transmission shaft, which results in undesirable loads in the transmission.
German Patent No. 35 15 928 A1 describes a known radial plain bearing which is located between two inertial masses which are movable in relation to one another. This plain bearing is located at a significant axial distance from the crankshaft of the internal combustion engine, so that, on account of the above-mentioned axial distance, wobbling movements which are applied to the end of the crankshaft facing the inertial mass device make themselves felt to a significant extent on the radial plain bearing perpendicular to the axis of rotation of the inertial masses, and accordingly the radial plain bearing is exposed to significant surface pressures. This problem is also basically encountered in the German patent discussed above, but the surface pressure on the radial plain bearing is counteracted by the axial clamping of the two inertial masses, although as mentioned above, that has its own additional disadvantages.